Construction of ternary heterostructured Ag/Ag2O@ZnO@g-C3N4 nanocomposite as an widened visible light photocatalyst for the organic oxidation

Two dimension g-C 3 N 4 was synthesized by thermal polymerization using mixture urea and melamine . The metal oxide Ag 2 O and ZnO were loaded to nanolayer of g-C 3 N 4 . The composites Ag/Ag 2 O@ZnO@g-C 3 N 4 were constructed by Ag 2 O and ZnO which were defined for p-type and n-type semiconductor to form heterojunctions . The samples were characterized by X ray diffraction(XRD), transmission electron microscopy(TEM), X ray photoelectron spectroscopy (XPS) and UV/Vis diffuse reflectance spectroscopy (UV–vis DRS). The experiment results indicate that Ag 2 O and ZnO were uniformly loaded to nanolayer of g-C 3 N 4 and heterojunction of Ag/Ag 2 O@ZnO@g-C 3 N 4 was constructed. The photocatalytic activity of Ag/Ag 2 O@ZnO@g-C 3 N 4 was characterized by degradation of methylene blue (MB) under the widened visible light-driven. The photodegradation efficiency of MB was 64.486%, 87.724%, 91.611%, 96.700% and 99.999% over g-C 3 N 4 , ZnO@g-C 3 N 4 , Ag/Ag 2 O@g-C 3 N 4 , Ag/Ag 2 O@ZnO@g-C 3 N 4 -1 and Ag/Ag 2 O@ZnO@g-C 3 N 4 -2, respectively. The results show that the photocatalytic activity of Ag/Ag 2 O@ZnO@g-C 3 N 4 was enhanced based on the p-n structure which decreased the recombination rates of photoinduced electron hole between metal oxide and g-C 3 N 4 . Finally, photocatalytic mechanism of Ag/Ag 2 O@ZnO@g-C 3 N 4 was discussed for ternary heterostructured catalysts. • Ag/Ag 2 O@ZnO@g-C 3 N 4 photocatalysts was fabricated via pyrolysis and hydrothermal method. • Ag/Ag 2 O@ZnO@g-C 3 N 4 exhibit a superior activity in comparison with single component. • The main active substances was defined as the hydroxyl radical (·OH). • The degradation mechanism by Ag/Ag 2 O@ZnO@g-C 3 N 4 by visible light irradiated system was demonstrated.